Hello, is there an equivalent or a way to implemen...

# graphql-kotlin

[jmfayard]

Hello,
is there an equivalent or a way to implement the @constraint directive from ApolloGraphQL?
https://www.apollographql.com/blog/backend/validation/graphql-validation-using-directives/

type SignUpInput {
  email: String! @constraint(format: "email", maxLength: 255)
  password: String! @constraint(maxLength: 255)
}

[Dariusz Kuc]

Hello 👋
Yes you can create custom directives -> https://opensource.expediagroup.com/graphql-kotlin/docs/schema-generator/customizing-schemas/directives#custom-directives

[jmfayard]

Thank you.
Following the official samples, I created an annotated ConstraintDirective and its ConstraintDirectiveWiring which I registered in a `KotlinDirectiveWiringFactory`which itself is registered as hooks inside a SchemaGeneratorConfig
But still the directive does not appear in the generated GraphQL Schema.
I'm using ktor.
Is there maybe some magic that works only with Spring Boot?

[Dariusz Kuc]

Sounds like it should work, can you share a repo?

[Shane Myrick]

Just to clarify, the @constraint directive you are referring to is a schema or server side directive and is logic that is applied to the field on every client operation with out them specifying anything. The HTTP framework should not matter.

Also it is not from Apollo, it is from the GitHub user confuser

https://github.com/confuser/graphql-constraint-directive

[jmfayard]

Hello, I shared a repo here

https://github.com/ExpediaGroup/graphql-kotlin/pull/1350

[Dariusz Kuc]

👍 I'll take a look today